From 24778be20f87d5aadb19624fc768b3159fa43efc Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Tue, 21 May 2013 20:36:35 -0600 Subject: spi: convert drivers to use bits_per_word_mask Fill in the recently added spi_master.bits_per_word_mask field in as many drivers as possible. Make related cleanups, such as removing any redundant error-checking, or empty setup callbacks. Signed-off-by: Stephen Warren Acked-by: H Hartley Sweeten Signed-off-by: Mark Brown --- drivers/spi/spi-xilinx.c | 16 ---------------- 1 file changed, 16 deletions(-) (limited to 'drivers/spi/spi-xilinx.c') diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index e1d76960742..f321bf95d7c 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -232,21 +232,6 @@ static int xilinx_spi_setup_transfer(struct spi_device *spi, return 0; } -static int xilinx_spi_setup(struct spi_device *spi) -{ - /* always return 0, we can not check the number of bits. - * There are cases when SPI setup is called before any driver is - * there, in that case the SPI core defaults to 8 bits, which we - * do not support in some cases. But if we return an error, the - * SPI device would not be registered and no driver can get hold of it - * When the driver is there, it will call SPI setup again with the - * correct number of bits per transfer. - * If a driver setups with the wrong bit number, it will fail when - * it tries to do a transfer - */ - return 0; -} - static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi) { u8 sr; @@ -377,7 +362,6 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem, xspi->bitbang.chipselect = xilinx_spi_chipselect; xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer; xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs; - xspi->bitbang.master->setup = xilinx_spi_setup; init_completion(&xspi->done); if (!request_mem_region(mem->start, resource_size(mem), -- cgit v1.2.3-70-g09d2 From 082339bc63cccf8ea49b1f3cf4ee39ce00742849 Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Tue, 4 Jun 2013 16:02:36 +0200 Subject: spi: spi-xilinx: Add run run-time endian detection Do not load endian value from platform data and rather autodetect it. Signed-off-by: Michal Simek Signed-off-by: Mark Brown --- drivers/mfd/timberdale.c | 1 - drivers/spi/spi-xilinx.c | 29 +++++++++++++++++++++-------- include/linux/spi/xilinx_spi.h | 1 - 3 files changed, 21 insertions(+), 10 deletions(-) (limited to 'drivers/spi/spi-xilinx.c') diff --git a/drivers/mfd/timberdale.c b/drivers/mfd/timberdale.c index 59e0ee247e8..0c1fcbc23d0 100644 --- a/drivers/mfd/timberdale.c +++ b/drivers/mfd/timberdale.c @@ -145,7 +145,6 @@ static struct spi_board_info timberdale_spi_8bit_board_info[] = { static struct xspi_platform_data timberdale_xspi_platform_data = { .num_chipselect = 3, - .little_endian = true, /* bits per word and devices will be filled in runtime depending * on the HW config */ diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index e1d76960742..bb6ae4ee7de 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -30,6 +30,7 @@ */ #define XSPI_CR_OFFSET 0x60 /* Control Register */ +#define XSPI_CR_LOOP 0x01 #define XSPI_CR_ENABLE 0x02 #define XSPI_CR_MASTER_MODE 0x04 #define XSPI_CR_CPOL 0x08 @@ -359,11 +360,12 @@ static const struct of_device_id xilinx_spi_of_match[] = { MODULE_DEVICE_TABLE(of, xilinx_spi_of_match); struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem, - u32 irq, s16 bus_num, int num_cs, int little_endian, int bits_per_word) + u32 irq, s16 bus_num, int num_cs, int bits_per_word) { struct spi_master *master; struct xilinx_spi *xspi; int ret; + u32 tmp; master = spi_alloc_master(dev, sizeof(struct xilinx_spi)); if (!master) @@ -396,13 +398,25 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem, xspi->mem = *mem; xspi->irq = irq; - if (little_endian) { - xspi->read_fn = xspi_read32; - xspi->write_fn = xspi_write32; - } else { + + /* + * Detect endianess on the IP via loop bit in CR. Detection + * must be done before reset is sent because incorrect reset + * value generates error interrupt. + * Setup little endian helper functions first and try to use them + * and check if bit was correctly setup or not. + */ + xspi->read_fn = xspi_read32; + xspi->write_fn = xspi_write32; + + xspi->write_fn(XSPI_CR_LOOP, xspi->regs + XSPI_CR_OFFSET); + tmp = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET); + tmp &= XSPI_CR_LOOP; + if (tmp != XSPI_CR_LOOP) { xspi->read_fn = xspi_read32_be; xspi->write_fn = xspi_write32_be; } + xspi->bits_per_word = bits_per_word; if (xspi->bits_per_word == 8) { xspi->tx_fn = xspi_tx8; @@ -466,14 +480,13 @@ static int xilinx_spi_probe(struct platform_device *dev) { struct xspi_platform_data *pdata; struct resource *r; - int irq, num_cs = 0, little_endian = 0, bits_per_word = 8; + int irq, num_cs = 0, bits_per_word = 8; struct spi_master *master; u8 i; pdata = dev->dev.platform_data; if (pdata) { num_cs = pdata->num_chipselect; - little_endian = pdata->little_endian; bits_per_word = pdata->bits_per_word; } @@ -505,7 +518,7 @@ static int xilinx_spi_probe(struct platform_device *dev) return -ENXIO; master = xilinx_spi_init(&dev->dev, r, irq, dev->id, num_cs, - little_endian, bits_per_word); + bits_per_word); if (!master) return -ENODEV; diff --git a/include/linux/spi/xilinx_spi.h b/include/linux/spi/xilinx_spi.h index 6f17278810b..333ecdfee0d 100644 --- a/include/linux/spi/xilinx_spi.h +++ b/include/linux/spi/xilinx_spi.h @@ -11,7 +11,6 @@ */ struct xspi_platform_data { u16 num_chipselect; - bool little_endian; u8 bits_per_word; struct spi_board_info *devices; u8 num_devices; -- cgit v1.2.3-70-g09d2 From 913b19660e166e718d419cccd753c3990881f17c Mon Sep 17 00:00:00 2001 From: Sachin Kamat Date: Fri, 31 May 2013 17:17:49 +0530 Subject: spi: spi-xilinx: Remove redundant platform_set_drvdata() Setting platform data to NULL is not necessary. Also fixes the following sparse warning: drivers/spi/spi-xilinx.c:508:35: warning: Using plain integer as NULL pointer Signed-off-by: Sachin Kamat Signed-off-by: Mark Brown --- drivers/spi/spi-xilinx.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/spi/spi-xilinx.c') diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index bb6ae4ee7de..b07b004cea1 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -534,7 +534,6 @@ static int xilinx_spi_probe(struct platform_device *dev) static int xilinx_spi_remove(struct platform_device *dev) { xilinx_spi_deinit(platform_get_drvdata(dev)); - platform_set_drvdata(dev, 0); return 0; } -- cgit v1.2.3-70-g09d2 From e33d085d11e54bc9fb07b2555cd104d8e7b3089b Mon Sep 17 00:00:00 2001 From: "dan.carpenter@oracle.com" Date: Sun, 9 Jun 2013 16:07:28 +0300 Subject: spi: spi-xilinx: cleanup a check in xilinx_spi_txrx_bufs() '!' has higher precedence than comparisons so the original condition is equivalent to "if (xspi->remaining_bytes == 0)". This makes the static checkers complain. xspi->remaining_bytes is signed and from looking at the code briefly, I think it might be able to go negative. I suspect that going negative may cause a bug, but I don't have the hardware and can't test. Signed-off-by: Dan Carpenter Signed-off-by: Mark Brown --- drivers/spi/spi-xilinx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/spi/spi-xilinx.c') diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 34d18dcfa0d..109a535b639 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -315,7 +315,7 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) } /* See if there is more data to send */ - if (!xspi->remaining_bytes > 0) + if (xspi->remaining_bytes <= 0) break; } -- cgit v1.2.3-70-g09d2 From e07619539017ac31004a038d1d886e2ed4d0e61a Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Wed, 10 Jul 2013 09:25:28 +0200 Subject: spi/xilinx: Revert master->setup function removal master->setup() must be initialized to be able to successfully run spi_bitbang_start() and satisfy if/else logic there. "spi: convert drivers to use bits_per_word_mask" (sha1: 24778be20f87d5aadb19624fc768b3159fa43efc) Signed-off-by: Michal Simek Signed-off-by: Mark Brown --- drivers/spi/spi-xilinx.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'drivers/spi/spi-xilinx.c') diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index fb56fcfdf65..09a94285259 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -233,6 +233,21 @@ static int xilinx_spi_setup_transfer(struct spi_device *spi, return 0; } +static int xilinx_spi_setup(struct spi_device *spi) +{ + /* always return 0, we can not check the number of bits. + * There are cases when SPI setup is called before any driver is + * there, in that case the SPI core defaults to 8 bits, which we + * do not support in some cases. But if we return an error, the + * SPI device would not be registered and no driver can get hold of it + * When the driver is there, it will call SPI setup again with the + * correct number of bits per transfer. + * If a driver setups with the wrong bit number, it will fail when + * it tries to do a transfer + */ + return 0; +} + static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi) { u8 sr; @@ -360,6 +375,7 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem, xspi->bitbang.chipselect = xilinx_spi_chipselect; xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer; xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs; + xspi->bitbang.master->setup = xilinx_spi_setup; init_completion(&xspi->done); if (!request_mem_region(mem->start, resource_size(mem), -- cgit v1.2.3-70-g09d2